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-rw-r--r--fs/crypto/fscrypt_private.h93
1 files changed, 93 insertions, 0 deletions
diff --git a/fs/crypto/fscrypt_private.h b/fs/crypto/fscrypt_private.h
new file mode 100644
index 000000000000..aeab032d7d35
--- /dev/null
+++ b/fs/crypto/fscrypt_private.h
@@ -0,0 +1,93 @@
+/*
+ * fscrypt_private.h
+ *
+ * Copyright (C) 2015, Google, Inc.
+ *
+ * This contains encryption key functions.
+ *
+ * Written by Michael Halcrow, Ildar Muslukhov, and Uday Savagaonkar, 2015.
+ */
+
+#ifndef _FSCRYPT_PRIVATE_H
+#define _FSCRYPT_PRIVATE_H
+
+#include <linux/fscrypto.h>
+
+#define FS_FNAME_CRYPTO_DIGEST_SIZE 32
+
+/* Encryption parameters */
+#define FS_XTS_TWEAK_SIZE 16
+#define FS_AES_128_ECB_KEY_SIZE 16
+#define FS_AES_256_GCM_KEY_SIZE 32
+#define FS_AES_256_CBC_KEY_SIZE 32
+#define FS_AES_256_CTS_KEY_SIZE 32
+#define FS_AES_256_XTS_KEY_SIZE 64
+#define FS_MAX_KEY_SIZE 64
+
+#define FS_KEY_DESC_PREFIX "fscrypt:"
+#define FS_KEY_DESC_PREFIX_SIZE 8
+
+#define FS_KEY_DERIVATION_NONCE_SIZE 16
+
+/**
+ * Encryption context for inode
+ *
+ * Protector format:
+ * 1 byte: Protector format (1 = this version)
+ * 1 byte: File contents encryption mode
+ * 1 byte: File names encryption mode
+ * 1 byte: Flags
+ * 8 bytes: Master Key descriptor
+ * 16 bytes: Encryption Key derivation nonce
+ */
+struct fscrypt_context {
+ u8 format;
+ u8 contents_encryption_mode;
+ u8 filenames_encryption_mode;
+ u8 flags;
+ u8 master_key_descriptor[FS_KEY_DESCRIPTOR_SIZE];
+ u8 nonce[FS_KEY_DERIVATION_NONCE_SIZE];
+} __packed;
+
+#define FS_ENCRYPTION_CONTEXT_FORMAT_V1 1
+
+/* This is passed in from userspace into the kernel keyring */
+struct fscrypt_key {
+ u32 mode;
+ u8 raw[FS_MAX_KEY_SIZE];
+ u32 size;
+} __packed;
+
+/*
+ * A pointer to this structure is stored in the file system's in-core
+ * representation of an inode.
+ */
+struct fscrypt_info {
+ u8 ci_data_mode;
+ u8 ci_filename_mode;
+ u8 ci_flags;
+ struct crypto_skcipher *ci_ctfm;
+ struct key *ci_keyring_key;
+ u8 ci_master_key[FS_KEY_DESCRIPTOR_SIZE];
+};
+
+#define FS_CTX_REQUIRES_FREE_ENCRYPT_FL 0x00000001
+#define FS_CTX_HAS_BOUNCE_BUFFER_FL 0x00000002
+
+struct fscrypt_completion_result {
+ struct completion completion;
+ int res;
+};
+
+#define DECLARE_FS_COMPLETION_RESULT(ecr) \
+ struct fscrypt_completion_result ecr = { \
+ COMPLETION_INITIALIZER((ecr).completion), 0 }
+
+
+/* crypto.c */
+int fscrypt_initialize(unsigned int cop_flags);
+
+/* keyinfo.c */
+extern int fscrypt_get_crypt_info(struct inode *);
+
+#endif /* _FSCRYPT_PRIVATE_H */